scholarly journals Detection roasting level of Lintong coffee beans by using euclidean distance

2021 ◽  
Vol 10 (6) ◽  
pp. 3072-3082
Author(s):  
Yohanssen Pratama ◽  
I Gde Eka Dirgayussa ◽  
Paian Fernando Simarmata ◽  
Mia Hotmaria Tambunan
Keyword(s):  
Euclidean Distance ◽  
Color Change ◽  
Roasted Coffee ◽  
Green Beans ◽  
Color Changes ◽  
Coffee Beans ◽  
Roasting Process ◽  
Roasted Coffee Beans ◽  
Light Medium ◽  
Coffee Roasting

Coffee roasting is the process by which raw coffee beans (green beans) are roasted until they reach a certain roast level. In general, the roast level of roasted coffee beans is divided into 3 levels, namely the roast level of light, medium and dark. One way to find out the roast level of roasted coffee beans is to see the color change of the coffee beans. However, it is very difficult to know the exact color conditions of each roast level of roasted coffee beans and this can be overcome by build an automatic coffee roasting equipment. In this research, an automatic coffee roaster was done with a system that is able to control the roasting temperature and stirring of coffee beans. This tool can also monitor the change in color of the coffee beans during the roasting process. The system that has been implemented can detect color changes and classify the level of dark roast of roasted coffee beans using the Euclidean distance algorithm. The Euclidean distance give a threshold to classified the roast level. The system accuracy for predicting coffee beans color at the level of dark roast is 90% and 80% for overall.

scholarly journals Temperature coverage simulation of horizontal cylinder type coffee roasting machine

2021 ◽  
Vol 922 (1) ◽  
pp. 012031
Author(s):  
F Fachruddin ◽  
S Syafriandi ◽  
R Fadhil
Keyword(s):  
Bulk Density ◽  
Horizontal Cylinder ◽  
Roasted Coffee ◽  
Actual Temperature ◽  
Coffee Beans ◽  
Roasting Process ◽  
Study Results ◽  
Roasting Temperature ◽  
Roasted Coffee Beans ◽  
Coffee Roasting

Abstract This study aims to simulate the temperature distribution of coffee roasting machines and study the profile of coffee beans roasted using a horizontal cylinder-type roaster. The coffee used in this study is arabica. The simulation method for the temperature estimation in the coffee roasting process uses the Solidworks Flow Simulation 2016 software, while the actual temperature measurement using a thermocouple is simulated with the Surfer software version 16. Furthermore, each stage of the coffee roasting process has been carried out, including the weight of the material, the roasting temperature, and the bulk density. The final step is to observe the profile of the roasted coffee beans at every minute of treatment. The study results indicate a difference between the approximate temperature simulation (top 176.85°C, bottom 191.97°C) and the actual temperature measured results (upper 214°C, bottom 220°C). The weight of the material (coffee green bean), the roasting temperature, and the bulk density during the test experienced regular movements from the beginning to the end of the treatment. The profile of roasted coffee beans shows a darker color movement along with the longer roasting time used. The profile of the roasted coffee beans will be beneficial in determining at which level of roasting you want (light, medium, medium-dark, dark).

scholarly journals Phytochemical Profile and Antioxidant Capacity of Coffee Plant Organs Compared to Green and Roasted Coffee Beans

Antioxidants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 93 ◽  
Author(s):  
Robert Acidri ◽  
Yumiko Sawai ◽  
Yuko Sugimoto ◽  
Takuo Handa ◽  
Daisuke Sasagawa ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Leaf Age ◽  
Total Phenolic ◽  
Coffee Plant ◽  
Roasted Coffee ◽  
Green Beans ◽  
Antioxidant Power ◽  
Plant Organs ◽  
Coffee Beans ◽  
Roasted Coffee Beans

The current study investigates the phytochemical composition of coffee plant organs and their corresponding antioxidant capacities compared to green and roasted coffee beans. HPLC analysis indicated that the investigated compounds were present in all organs except mangiferin, which was absent in roots, stems and seeds, and caffeine, which was absent in stems and roots. Total phytochemicals were highest in the green beans (GB) at 9.70 mg g−1 dry weight (DW), while roasting caused a 66% decline in the roasted beans (RB). This decline resulted more from 5–CQA and sucrose decomposition by 68% and 97%, respectively, while caffeine and trigonelline were not significantly thermally affected. Roasting increased the total phenolic content (TPC) by 20.8% which was associated with an increase of 68.8%, 47.5% and 13.4% in the antioxidant capacity (TEAC) determined by 2,2–diphenyl–1–picryl hydrazyl radical (DPPH), 2,2–azino bis (3–ethyl benzothiazoline–6–sulphonic acid) radical (ABTS) and Ferric ion reducing antioxidant power (FRAP) assays, respectively. Amongst the leaves, the youngest (L1) contained the highest content at 8.23 mg g−1 DW, which gradually reduced with leaf age to 5.57 mg g−1 DW in the oldest (L6). Leaves also contained the highest TPC (over 60 mg g−1 GAE) and exhibited high TEAC, the latter being highest in L1 at 328.0, 345.7 and 1097.4, and least in L6 at 304.6, 294.5 and 755.1 µmol Trolox g−1 sample for the respective assays. Phytochemical accumulation, TPC and TEAC were least in woody stem (WS) at 1.42 mg g−1 DW; 8.7 mg g−1 GAE; 21.9, 24.9 and 110.0 µmol Trolox g−1 sample; while herbaceous stem (HS) contained up to 4.37 mg g−1 DW; 27.8 mg g−1 GAE; 110.9, 124.8 and 469.7 µmol Trolox g−1 sample, respectively. Roots contained up to 1.85 mg g−1 DW, 15.8 mg−1 GAE and TEAC of 36.8, 41.5 and 156.7 µmol Trolox g−1 sample. Amongst the organs, therefore, coffee leaves possessed higher values than roasted beans on the basis of phytochemicals, TPC and TEAC. Leaves also contain carotenoids and chlorophylls pigments with potent health benefits. With appropriate processing methods, a beverage prepared from leaves (coffee leaf tea) could be a rich source of phytochemicals and antioxidants with therapeutic and pharmacological values for human health.

scholarly journals Perancangan, Implementasi Monitoring dan Kontrol Alat Pemanggang Kopi

ELKHA ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 69
Author(s):  
Friyogi Tampubolon ◽  
Yohanssen Pratama ◽  
I Gde Eka Dirgayussa
Keyword(s):  
Raspberry Pi ◽  
Roasted Coffee ◽  
3D Design ◽  
Roasting Machine ◽  
Coffee Beans ◽  
Human Labor ◽  
Temperature Parameter ◽  
The Difference ◽  
Roasted Coffee Beans ◽  
Coffee Roasting

Coffee roasting is the process of removing the water that is exist in the coffee beans. Roasted coffee beans will change weight and give a nice aroma and taste. The longer the coffee beans are roasted, the color of the coffee beans will continue getting darker blackish brown. The roasting level of coffee beans is determined from the change in color of coffee beans starting from light, medium and dark. Roasting coffee beans that develop on a home industry scale is still manual, that is, using more human labor in its operation. Therefore, this research will be made an automatic coffee roasting machine using a heater to heating the coffee beans, a DC motor to stir roasted coffee beans and a webcam to monitor changes in the color of coffee beans when roasted. Components of heating elements and motors controlled by Arduino Mega 2560 microcontroller while the webcam is connected with Raspberry Pi 3. As a component of performance that has been met with sensors as data collectors, microcontrollers as data processors and actuators as control systems. In this researh 3D modeling for a roasting container is done using SketchUp 3D design software. The results of the coffee roasting machine can meet the requirements of the system designed in accordance with the roasting level desired by the user and the thermocoupel give a better result in reading the temperature parameter compared to infrared thermometer. In 4,5 minutes the difference reading in temperature reach 27,50C between two sensors.

scholarly journals Influence of Altitude on Caffeine, 5-Caffeoylquinic Acid, and Nicotinic Acid Contents of Arabica Coffee Varieties

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Bealu Girma ◽  
Abera Gure ◽  
Feyisa Wedajo
Keyword(s):  
Nicotinic Acid ◽  
High Performance ◽  
Array Detector ◽  
Roasted Coffee ◽  
Arabica Coffee ◽  
Caffeoylquinic Acid ◽  
Coffee Beans ◽  
Roasting Process ◽  
Target Analytes ◽  
Roasted Coffee Beans

The influence of altitude on caffeine, 5-caffeoylquinic acid (5-CQA), and nicotinic acid contents of Arabica coffee varieties grown in Southwest Ethiopia was investigated. High-performance liquid chromatography with diode array detector (HPLC-DAD) was used for the determination of the target analytes. Coffee samples were collected from four coffee varieties, named as 74112, 7454, 7440, and 74110, which are cultivated in high, mid, and low altitudes in the study area. The findings of the study showed that the contents of caffeine and 5-CQA in both raw and roasted coffee beans decrease as the growing altitude increases and, thus, for all varieties, their highest concentrations were recorded in lowland coffee beans. Nevertheless, the contents of nicotinic acid increase as the altitude rises and, thus, the highest nicotinic acid content was recorded in highland coffee samples. Besides, after roasting, the contents of caffeine were increased, whereas the contents of 5-CQA were lowered, indicating the possibility of its degradation during the roasting process. Both green and roasted coffee beans also contained relatively higher concentrations of nicotinic acids. Other than the growing altitudes, the contents of caffeine, 5-CQA, and nicotinic acid in coffee beans also vary with coffee varieties. Therefore, coffee varieties that are cultivated at various altitudes may have different biochemical compositions such as caffeine, CGAs, and nicotinic acid that could greatly influence the flavor, aroma, and stimulating attributes of coffee cup quality as well as dietary benefits.

scholarly journals Comparison of the Antioxidant Activities and Volatile Compounds of Coffee Beans Obtained Using Digestive Bio-Processing (Elephant Dung Coffee) and Commonly Known Processing Methods

Antioxidants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 408
Author(s):  
Mesfin Haile ◽  
Hyung Min Bae ◽  
Won Hee Kang
Keyword(s):  
Antioxidant Activity ◽  
Volatile Compounds ◽  
Green Coffee ◽  
Roasted Coffee ◽  
Green Beans ◽  
Processing Methods ◽  
Green Coffee Beans ◽  
Coffee Beans ◽  
Roasted Coffee Beans ◽  
Elephant Dung

There are different types of coffee processing methods. The wet (WP) and dry processing (DP) methods are widely practiced in different parts of coffee-growing countries. There is also a digestive bioprocessing method in which the most expensive coffee is produced. The elephant dung coffee is produced using the digestive bioprocessing method. In the present experiment, the antioxidant activity and volatile compounds of coffee that have been processed using different methods were compared. The antioxidant activity, total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC) of green coffee beans from all treatments were higher as compared to roasted coffee beans. Regarding the green coffee beans, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of elephant dung coffee beans was higher as compared to that of the DP and WP coffee beans. The green coffee beans had higher DPPH activity and ferric reducing antioxidant power (FRAP) value compared to the roasted coffee beans. The green beans of elephant dung coffee had a high TPC than the beans obtained by WP and DP methods. TFC in elephant dung coffee in both green and roasted condition was improved in contrast to the beans processed using dry and wet methods. The elephant dung coffee had an increased TTC in comparison to the DP and WP coffee (green beans). About 37 volatile compounds of acids, alcohols, aldehydes, amide, esters, ethers, furans, furanones, ketones, phenols, pyrazines, pyridines, Heterocyclic N, and pyrroles functional classes have been found. Some of the most abundant volatile compounds detected in all treatments of coffee were 2-furanmethanol, acetic acid, 2-methylpyrazine, 2,6-dimethylpyrazine, pyridine, and 5-methylfurfural. Few volatile compounds have been detected only in elephant dung coffee. The principal component analysis (PCAs) was performed using the percentage of relative peak areas of the volatile compound classes and individual volatile compounds. This study will provide a better understanding of the impacts of processing methods on the antioxidants and volatile compounds of coffee.

scholarly journals Effect of Roasting Conditions on Concentration in Elements of Vietnam Robusta Coffee

2014 ◽  
Vol 18 (2) ◽  
pp. 19-34 ◽  
Author(s):  
Tran Van Cuong ◽  
Liu Hong Ling ◽  
Guo Kang Quan ◽  
Shang Jin ◽  
Song Shu Jie ◽  
...  
Keyword(s):  
Absorption Method ◽  
Roasted Coffee ◽  
Robusta Coffee ◽  
Flame Atomic Absorption ◽  
Zn Concentration ◽  
Coffee Beans ◽  
Roasting Process ◽  
Roasting Temperature ◽  
Roasted Coffee Beans ◽  
Pb Concentration

Abstract Vietnam Robusta Coffee was roasted at different roasting degree and roasting temperature and 9 element concentrations (K, Mg, Ca, Na, Fe, Cu, Mn, Zn and Pb) of roasted coffee were analyzed by Flame atomic absorption method (FAAS) in this study. The results showed that the concentrations were ranged in 1447.97 ~ 1342.10 (mg/100g), 768.22 ~ 1259.44 (μg/g),10.35 ~ 13.15 (μg/g), and 17.38 ~ 20.97 (μg/g) for element of K, Ca, Cu and Mn in green and roasted coffee beans, respectively. All determined elements were the smallest value in green coffee, then increased with increasing roasting level and reached the highest value in Spain roast (roasting temperature of 250°C). Mg concentration ranged in 682.70 ~ 3647.73 (μg/g); Fe concentration ranged in 37.20 ~ 53.44 (μg/g); Zn concentration ranged in 5.97 ~ 6.89 (μg/g) and Pb concentration ranged in 2.18 ~ 15.04 (μg/100g). Concentrations of all determined elements didn’t change with the increased roasting process.

scholarly journals Changes of physical properties of coffee beans during roasting

2012 ◽  
pp. 21-31 ◽  
Author(s):  
Marija Jokanovic ◽  
Natalija Dzinic ◽  
Biljana Cvetkovic ◽  
Slavica Grujic ◽  
Bozana Odzakovic
Keyword(s):  
Heating Time ◽  
Coffee Bean ◽  
Roasted Coffee ◽  
Colour Parameter ◽  
Coffee Beans ◽  
Roasting Process ◽  
Roasting Temperature ◽  
Physical Changes ◽  
Light Medium

The effects of heating time on physical changes (weight, volume, texture and colour) of coffee beans (Outspan and Guaxupe coffee) were investigated. The roasting temperature of both samples was 170?C and samples for analysis were taken at the intervals of 7 minutes during 40 minutes of roasting. Total weight loss at the end of the roasting process was 14.43 % (light roasted) and 17.15 % (medium to dark roasted) for Outspan and Guaxupe coffee beans, respectively. Significant (P < 0.05) changes in the coffee bean breaking force values were noted between the 7th and 14th minutes, and statistically not significant (P > 0.05) between the 35th and 40th minutes of the roasting. According to the L* colour parameter as a criterion for the classification of roasted coffee colour (light, medium, dark), the Outspan sample was medium and Guaxupe sample was dark roasted.

scholarly journals Analysis of Volatile Compounds in Coffee Prepared by Various Brewing and Roasting Methods

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1347
Author(s):  
Ja-Myung Yu ◽  
Mingi Chu ◽  
Hyunbeen Park ◽  
Jooyeon Park ◽  
Kwang-Geun Lee
Keyword(s):  
Volatile Compounds ◽  
Extraction Methods ◽  
Measured Signal ◽  
Roasted Coffee ◽  
Green Coffee Beans ◽  
Coffee Beans ◽  
Espresso Coffee ◽  
Roasting Temperature ◽  
Roasted Coffee Beans ◽  
Significant Factors

Volatile compounds of coffee brewed under various roasting conditions and by different brewing methods were analyzed. Green coffee beans (Coffea arabica) were roasted at 235 °C for 13 min, 240 °C for 15 min, and 245 °C for 17 min. Roasted coffee beans were ground into particles of three different sizes (710, 500, and 355 μm) and brewed by an espresso coffee machine and the cold brew method. Three types of water (filtered, tap, and bottled) were used for coffee extraction. SPME-GC-MS results indicated that increasing the roasting temperature and time increased the levels of 2,2′-methylene-bis-furan, guaiacol, and 4-ethylguaiacol (p < 0.05) and decreased the levels of furfural (p < 0.05). Grind size was inversely proportional to the measured signal of volatiles by GC-MS (p < 0.05). The measured GC/MS intensities of 2-methylpyrazine, 2,5-dimethylpyrazine, and 2-methoxy-4-vinylphenol were significantly higher in coffee brewed with filtered water (p < 0.05) than tap and bottled water. 2-Methylpyrazine, 1-methylpyrrole, and 2-acetylfuran were the most abundant components in the cold brew. Overall, roasting conditions and extraction methods were determined to be significant factors for volatile compounds in coffee. This is the first study showing the analysis of volatile compounds in coffee according to various types of water and extraction methods, such as espresso and cold brew coffee.

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